CNN — The video looks like a gun advertisement – on steroids. Shot in the style of a music video, with quick edits and a pulsating beat, three athletic looking men test fire a variety of machine guns, rocket launchers, assault rifles and handguns. Surrounded by bearded soldiers in military gear, the three men are shown smiling and laughing, seemingly having a good time. Except, this is not your run-of-the-mill gun range outing. Ultimate Fighting Championship (UFC) fighters Kamaru Usman, Justin Gaethje and Henry Cejudo are the trio in a video posted online by the notorious Chechen leader Ramzan Kadyrov...